ImGui¶

The ImGui Lua wrapper is a package that provides a Lua interface for the popular ImGui module. It allows developers to create in-game user interfaces using the familiar Lua programming language. The wrapper offers a simple and easy-to-use API that mirrors the C++ API of the ImGui module. This package provides a wide range of UI elements and widgets, customizable styling options, and support for multiple languages and internationalization. With this package, developers can easily add robust UI functionality to their games and applications written in Lua. The package also supports advanced layout and positioning options and built-in support for common UI interactions such as drag and drop, and context menus.

Some of the key features include:

A wide range of UI elements and widgets
Customizable styling options
Support for multiple languages and internationalization
Advanced layout and positioning options
Support for keyboard and mouse input
Built-in support for common UI interactions such as drag and drop, and context menus.

Reference¶

ImGui.setGlobalWindowPadding(x, y)¶

Sets the global window padding for all windows.

Parameters:

x (number) – Padding for the x-axis.
y (number) – Padding for the y-axis.

ImGui.setGlobalWindowRounding(r)¶

Sets the global window rounding for all windows.

Parameters:: r (number) – Rounding value.

ImGui.setGlobalFramePadding(x, y)¶

Sets the global frame padding for all windows.

Parameters:

x (number) – Padding for the x-axis.
y (number) – Padding for the y-axis.

ImGui.setGlobalFrameRounding(r)¶

Sets the global frame rounding for all windows.

Parameters:: r (number) – Rounding value.

ImGui.setGlobalItemSpacing(x, y)¶

Sets the global item spacing for all windows.

Parameters:

x (number) – Spacing for the x-axis.
y (number) – Spacing for the y-axis.

ImGui.setGlobalItemInnerSpacing(x, y)¶

Sets the global item inner spacing for all windows.

Parameters:

x (number) – Inner spacing for the x-axis.
y (number) – Inner spacing for the y-axis.

ImGui.setGlobalIndentSpacing(value)¶

Sets the global indent spacing for all windows.

Parameters:: value (number) – Indent spacing value.

ImGui.setGlobalScrollbarSize(value)¶

Sets the global scrollbar size for all windows.

Parameters:: value (number) – Scrollbar size value.

ImGui.setGlobalScrollbarRounding(value)¶

Sets the global scrollbar rounding for all windows.

Parameters:: value (number) – The value of the scrollbar rounding.

ImGui.setGlobalGrabMinSize(value)¶

Sets the global minimum width/height of a grab box for slider/scrollbar for all windows.

Parameters:: value (number) – The value of the minimum grab.

ImGui.setGlobalGrabRounding(value)¶

Sets the global radius of grabs corners rounding for all windows. Set to 0.0 to have rectangular slider grabs.

Parameters:: value (number) – The value of grabs corners rounding.

ImGui.beginDialog(text, x, y, flags)¶

Begins a new dialog.

Parameters:

text (str) – The title of the dialog.
x (number) – The x coordinate of the dialog (optional).
y (number) – The y coordinate of the dialog (optional).
flags (WindowFlags) – Configuration flags.

ImGui.endDialog()¶: Ends the current dialog.

ImGui.beginMainMenuBar()¶

Begins the main menu bar. See Creating Menu bars example.

Returns:: Return true if the main menu bar is open, otherwise false.
Return type:: boolean

ImGui.endMainMenuBar()¶: Ends the current main menu bar.

ImGui.beginMenuBar()¶

Begins a new menu-bar inside current window.

To be displayed correctly, the dialog parent needs to have the ImGui.WindowFlags.MenuBar flag enabled. See Creating Menu bars example.

Returns:: Return true if the menu bar is open, otherwise false.
Return type:: boolean

ImGui.endMenuBar()¶: Ends the current menu bar.

ImGui.beginMenu(label)¶

Begins a new menu.

Parameters:: label (str) – the label of the menu. See Creating Menu bars example
Returns:: Return true if the menu is open, otherwise false.
Return type:: boolean

ImGui.endMenu()¶: Ends the current menu.

ImGui.menuItem(mainLabel, secondaryLabel)¶

Creates a new menu item.

Parameters:

mainLabel (str) – The main label of the menu item.
secondaryLabel (str) – The secondary label of the menu item.

Returns:

Return true if the menu item is pressed, otherwise false.

Return type:

boolean

ImGui.beginChild(label)¶

Begins a child window. See Using Groups and Child for a full example

Parameters:: label (str) – the label of the child window.

ImGui.endChild()¶: Ends the current child window.

ImGui.beginGroup()¶: Begins a new group of items. See Using Groups and Child for a full example

ImGui.endGroup()¶: Ends the current group of items.

ImGui.beginTable(mode, number)¶

Begins a new table. See Using Tables for a full example.

Parameters:

mode (str) – The mode of the table.
number (number) – The number of the table.

Returns:

Return true if the table is open, otherwise false.

Return type:

boolean

ImGui.endTable()¶: Ends the current table.

ImGui.tableNextRow()¶: Appends into into the next row of the table.

ImGui.tableNextColumn()¶: Appends into into the next column of the table.

ImGui.tableNextRow(): Moves to the next row in the table.

ImGui.moveToNextColumn()¶: Moves to the next column in the table.

ImGui.tableSetCell(label)¶

Sets a cell in the table.

Parameters:: label (str) – The label of the cell.

ImGui.createColumns(numberCols)¶

Creates the specified number of columns in the current window.

Parameters:: numberCols (number) – The number of columns.

ImGui.beginTabBar(label, flags)¶

Begins a new tab bar. See Using the Tab Bar element. for a full example.

Parameters:

label (str) – The label of the tab bar.
flags (TabBarFlags) – Configuration flags.

Returns:

Return true if the tab bar is open, otherwise false.

Return type:

boolean

ImGui.endTabBar()¶: Ends the current tab bar.

ImGui.beginTabItem(label, flags)¶

Begins a new tab item.

Parameters:

label (str) – The label of the tab item.
flags (TabBarFlags) – Configuration flags.

Returns:

Return true if the tab item is open, otherwise false.

Return type:

boolean

ImGui.endTabItem()¶: Ends the current tab item.

ImGui.beginTooltip()¶: Begins a new tooltip.

ImGui.endTooltip()¶: Ends the current tab item.

ImGui.beginPopup(label, flags)¶

Begins a new popup window. See Creating different types of popups. for a full example.

Parameters:

label (str) – The label of the pop up item.
flags (PopupFlags) – Configuration flags.

Returns:

Return true if the popup is open, otherwise false.

Return type:

boolean

ImGui.endPopup()¶: Ends the current popup window.

ImGui.openPopup()¶: Opens a popup window identified by the label.

ImGui.closeCurrentPopup()¶: Closes the current popup window.

ImGui.beginPopupModal(label, flags)¶

Begins a new modal popup window.

Parameters:

label (str) – The label of the pop up modal item.
flags (PopupFlags) – Configuration flags.

Returns:

Return true if the popup is open, otherwise false.

Return type:

boolean

ImGui.text(text)¶

Displays text to the current window.

Parameters:: text (str) – The text to be displayed.

ImGui.textColored(text, color)¶

Displays text to the current window with a given color.

Parameters:

text (str) – the text to be displayed.
color (WidgetColor) – An instance of WidgetColor.

ImGui.textWrapped(text)¶

Displays wrapped text to the current window

Parameters:: text (str) – The text to be displayed.

ImGui.inputText(label, widgetString, flags)¶

Creates a text input widget.

Parameters:

label (str) – the label to add to the input widget.
widgetString (WidgetString) – An intance of WidgetString to interact with the inputText widget.
flags (InputTextFlags) – The flags to be used for the input label (optional).

Usage:

local gui = require 'engine/imgui'
widgetString = gui.WidgetString:new(32, "")
gui.inputText("your name", widgetString)

ImGui.inputNumber(label, widgetNumber, flags)¶

Creates a number input widget.

Parameters:

label (str) – the label to add to the input widget.
widgetNumber (WidgetNumber) – An intance of WidgetString to interact with the inputNumber widget.
flags (InputTextFlags) – The flags to be used for the input label (optional). They are the same for InputText.

Usage:

local gui = require 'engine/imgui'
widgetNumber = gui.WidgetNumber:new(42)
gui.inputNumber("Answer to The Ultimate Question of Life", widgetNumber)

ImGui.bulletText(text)¶

Creates a bullet point with accompanying text.

Parameters:: text (str) – The text to display next to the bullet point.

ImGui.progressBar(status)¶

Creates a new progress bar.

Parameters:: status (number) – Progress status (0.0f to 1.0f) to represent in the progress bar.

ImGui.sliderFloat(label, number, minValue, maxValue, format, flags)¶

Creates a new float slider.

Parameters:

label (str) – the label to add to the slider.
number (WidgetNumber) – The widgetNumber to use as storage.
minValue (number) – the minimum value for the slider.
maxValue (number) – the maximum value for the slider.
format (str) – format of the string in the slider. The default if omitted is “%f”.
flags (SliderFlags) – The flags to be used for the slider (optional).

ImGui.sliderInt(label, number, minValue, maxValue, format, flags)¶

Creates a new integer slider.

Parameters:

label (str) – The label to add to the slider.
number (WidgetNumber) – The widgetNumber to use as storage.
minValue (number) – The minimum value for the slider.
maxValue (number) – The maximum value for the slider.
format (str) – The format of the string in the slider. The default if omitted is “%d”.
flags (SliderFlags) – The flags to be used for the slider (optional).

ImGui.sliderVector3(label, widgetVector3, minValue, maxValue, format, flags)¶

Creates a set of three sliders for manipulating a vector3 object.

Parameters:

label (str) – The label to display next to the sliders.
widgetVector3 (WidgetVector3) – The vector3 widget object.
minValue (number) – The minimum value for the slider.
maxValue (number) – The maximum value for the slider.
format (str) – The format of the string in the slider. The default if omitted is “%f”.
flags (SliderFlags) – The flags to be used for the slider (optional).

ImGui.button(text, width, height)¶

Creates a new button.

Parameters:

text (str) – The text to be displayed on the button.
width (number) – The width of the button (optional).
height (number) – The height of the button (optional).

Returns:

Returns true if the button was clicked, otherwise false.

Return type:

boolean

ImGui.logButtons()¶: Logs button events in the ImGui interface.

ImGui.logToClipboard()¶: Logs the current ImGui interface to the clipboard. Useful for debugging.

ImGui.logFinish()¶: Stops logging events in the ImGui interface.

ImGui.logText(text)¶

Logs a text in the ImGui interface.

Parameters:: text (str) – the text to log

ImGui.separator()¶: Adds an horizontal separator between items.

ImGui.spacing()¶: Adds horizontal spacing between items.

ImGui.sameLine(spacing, offset)¶

The next item will be created on the same line.

Parameters:

spacing (number) – The spacing between items in pixels. If not given, the default spacing is used.
offset (number) – The X position where the next item should start in window coordiantes. If not given, the item is placed right after the previous one.

ImGui.selectable(text, flags)¶

Creates a selectable item.

Parameters:

text (str) – Text in the selectable item.
flags (SelectableFlags) – Configuration flags.

ImGui.checkbox(label, number)¶

Creates a new checkbox.

Parameters:

label (str) – The label of the checkbox.
number (WidgetNumber) – The widgetNumber to use as storage.

ImGui.checkboxFlags(label, flags)¶

Creates a new checkbox to enable/disable flags.

Parameters:

label (str) – The label of the checkbox.
flags (ConfigFlags) – Configuration flags.

ImGui.combo(label, number, items)¶

Creates a combo box with a list of items to choose from.

are indexed from 0 and arrays in Lua are indexed from 1. You will need to offset the arrays.

Parameters:

label (str) – The label of the combo box.
number (WidgetNumber) – The widgetNumber to use as storage. Note that arrays in ImGUI
items (array) – An array of strings to use as options.

ImGui.collapsingHeader(label)¶

Creates a collapsing header with a given label.

Parameters:: label (str) – The label of the header.
Returns:: Return true if the header is open, false if it is closed.
Return type:: boolean

ImGui.treeNode(label)¶

Creates a tree node.

Parameters:: label (str) – The label of the tree node.
Returns:: A boolean indicating whether the tree node is open.
Return type:: boolean

Usage:

local gui = require 'engine/imgui'
local TreeController = Class.new(Entity)

function TreeController:rendergui()
    gui.beginDialog("Tree Example")

    if gui.treeNode("Click to expand") then
        if gui.isItemToggledOpen() then
            gui.text("Just opened!")
        end
        gui.text("Some content...")
        gui.treePop()
    end

    gui.endDialog()
end
return TreeController

ImGui.treePop()¶

Ends the current tree node.

Called after treeNode(), it ends a tree node and automatically pops it from the ImGui tree structure.

ImGui.treePush(label)¶

Add a tree node to the GUI with the given label.

Parameters:: label (str) – The label to display on the tree node.

ImGui.colorPicker(label, color, flag)¶

Creates a color picker.

Parameters:

label (str) – The label of the color picker.
color (WidgetColor) – An instance of WidgetColor.
flag (ColorEditFlags) – User given flags to change the behaviour the behaviour of the widget.

Usage:

local gui = Nk.ImGui
gui.beginDialog("Color picker")
gui.colorPicker("Pick a color", color1)
gui.spacing()
gui.colorEdit("Edit a color", color2)
gui.endDialog()

ImGui.colorEdit(label, color, flag)¶

Creates a color edit. Similar to ColorPicker

Parameters:

label (str) – The label of the color picker.
color (WidgetColor) – An instance of WidgetColor.
flag (ColorEditFlags) – User given flags to change the behaviour of the widget.

ImGui.setNextWindowPos(x, y)¶

Sets the position of the next window.

Parameters:

x (number) – The x-coordinate of the window position.
y (number) – The y-coordinate of the window position.

ImGui.setNextWindowSize(x, y)¶

Sets the size of the next window.

Parameters:

x (number) – Width of the window.
y (number) – Height of the window.

ImGui.setNextWindowContentSize(x, y)¶

Sets the content size of the ColorEditFlagsnext window.

Parameters:

x (number) – Width of the window content
y (number) – Height of the window content

ImGui.setNextWindowSizeConstraints(x, y)¶

Sets the size constraints of the next window.

Parameters:

x (number) – Minimum width of the window.
y (number) – Minimum height of the window.

ImGui.setNextWindowCollapsed(collapsed)¶

Sets the collapsed state of the next window.

Parameters:: collapsed (boolean) – Whether the window should be collapsed or not.

ImGui.setNextWindowFocus(focused)¶

Sets the focus state of the next window.

Parameters:: focused (boolean) – Whether the window should be focused or not.

ImGui.setNextWindowBgAlpha(alpha)¶

Sets the background alpha value of the next window.

Parameters:: alpha (number) – The alpha value of the background, between 0 and 1.

ImGui.isItemHovered()¶

Determines if the current item is hovered by the mouse cursor. For an example, see Accesing item states..

Returns:: True if the current item is being hovered by the mouse cursor, false otherwise.
Return type:: boolean

ImGui.isItemClicked()¶

Determines if the current item has been clicked. For an example, see Accesing item states..

Returns:: True if the current item has been clicked, false otherwise.
Return type:: boolean

ImGui.isItemToggledOpen()¶

Determines if the current item is open. For an example, see Accesing item states..

Returns:: True if the current item is toggled open, false otherwise.
Return type:: boolean

ImGui.isMouseClicked(event)¶

Returns true if the mouse was clicked on the given event.

Parameters:: event (MouseButton) – The event for which to check for a mouse click.

ImGui.setMouseCursor(cursor)¶

Sets the mouse cursor to the given cursor type.

Parameters:: cursor (MouseCursor) – The cursor type to set.

class ImGui.WidgetString¶

A class to internally store strings to be used in the Lumino environment.

new(length, initialValue)¶

Creates a new WidgetString object with the given length and initial value.

Parameters:

length (number) – The lenght (in btyes) of the buffer where the string is stored.
initialValue (str) – The intial value of the string.

getValue()¶

Retrieves the value stored inside an instance of WidgetString.

Returns:: The string stored inside the instance of WidgetString.
Return type:: str

class ImGui.WidgetNumber¶

A class to internally store numbers to be used in the Lumino Lua environment.

new(initialValue)¶

Creates a new WidgetNumber object with the given initial value

Parameters:: initialValue (number) – The initial value stored internally.

getValue()¶

Retrieves the value stored inside an instance of WidgetNumber.

Returns:: The value interally stored inside the widget number.
Return type:: number

setValue(value)¶

Sets a new internal value to an instance of WidgetNumber.

Parameters:: value (number) – The value to set the widget number to.

class ImGui.WidgetVector3¶

A class to internally store a 3D vector to be used in the Lumino Lua environment.

new(x, y, z)¶

Creates a new WidgetVector3 object with the given initial values for x, y, z.

Parameters:

x (number) – The initial x component value.
y (number) – The initial y component value.
z (number) – The initial z component value.

Returns:

A new WidgetVector3 instance.

Return type:

WidgetVector3

getValue()¶

Retrieves the vector components stored inside an instance of WidgetVector3.

Returns:: The x, y, z components stored in the widget.
Return type:: number or number or number

setValue(x, y, z)¶

Sets new internal values for the x, y, z components of an instance of WidgetVector3.

Parameters:

x (number) – The x component to set.
y (number) – The y component to set.
z (number) – The z component to set.

class ImGui.WidgetColor¶

A class to internally link numbers to be used in the Dear ImGui api from the Lumino codebase to Lua environment.

new(r, g, b, a)¶

Creates a new WidgetColor object with the given RGBA values. The RGBA values range from 0 to 1.

Parameters:

r (number) – The red color component channel.
g (number) – The green color component channel.
b (number) – The blue color component channel.
a (number) – The alpha color component channel.

Returns:

A new WidgetColor instance.

Return type:

WidgetColor

getValue()¶

Retrieves the RGBA components stored inside an instance of WidgetColor. The RGBA values range from 0 to 1.

Returns:: The r, g, b, a components stored in the widget.
Return type:: number or number or number or number

setValue(r, g, b, a)¶

Sets new internal values for the r, g, b, a components of an instance of WidgetColor. The RGBA values range from 0 to 1.

Parameters:

r (number) – The r component to set.
g (number) – The g component to set.
b (number) – The b component to set.
a (number) – The a component to set.

class ImGui.ImGui¶

class ImGui.BackendFlags¶

Enumeration of the available backend flags.

Name	Description
None	No flag set.
HasGamepad	Backend platform supports gamepad and currently has one connected.
HasMouseCursors	Backend platform supports honoring GetMouseCursor() value to change the OS cursor shape.
HasSetMousePos	Backend platform supports io.WantSetMousePos requests to reposition the OS mouse position (only used if ImGuiConfigFlags_NavEnableSetMousePos is set).
RendererHasVtxOffset	Backend renderer supports ImDrawCmd::VtxOffset. This enables output of large meshes (64K+ vertices) while still using 16-bit indices.

class ImGui.ConfigFlags¶

Enumeration of the available configuration flags.

Name	Description
None	No flag set.
NavEnableKeyboard	Enable keyboard controls.
NavEnableGamepad	Enable gamepad controls.
NavEnableSetMousePos	Enable mouse repositioning requests with io.WantSetMousePos.
NavNoCaptureKeyboard	Disable keyboard capture by ImGui.
NoMouse	Disable mouse controls.
NoMouseCursorChange	Disable mouse cursor change requests.
IsSRGB	Enable sRGB gamma correction.
IsTouchScreen	Enable touch screen controls.

class ImGui.WindowFlags¶

Enumeration of the available window flags.

Name	Description
None	No flag set.
NoTitleBar	Window doesn’t have a title bar.
NoResize	Window can’t be resized.
NoMove	Window can’t be moved.
NoScrollbar	Window has no scrollbar.
NoScrollWithMouse	Window scrollbar doesn’t respond to mouse scrolling.
NoCollapse	Window can’t be collapsed.
AlwaysAutoResize	Window should resize to its content every frame.
ShowBorders	Window has borders.
NoSavedSettings	Never save settings (inodependent of ImGuiConfigFlags_NoSaveSettings).
NoMouseInputs	Window will not receive mouse inputs.
MenuBar	Window has a menu-bar.
HorizontalScrollbar	Window has a horizontal scrollbar.
NoFocusOnAppearing	Window doesn’t take focus when first appearing.
NoBringToFrontOnFocus	Window doesn’t bring to front when taking focus.
AlwaysVerticalScrollbar	Window has a vertical scrollbar.
AlwaysHorizontalScrollbar	Window has a horizontal scrollbar.
AlwaysUseWindowPadding	Ensure child windows without border uses style.WindowPadding (ignored by default for non-bordered child windows, because more convenient).
NoNavInputs	No gamepad/keyboard navigation within the window.
NoNavFocus	No focusing toward this window with gamepad/keyboard navigation (e.g. skipped by CTRL+TAB).
UnsavedDocument	Display a dot next to the title. When used in a tab/docking context, tab is selected when clicking the X + closure is not assumed (will wait for user to stop submitting the tab). Otherwise closure is assumed when pressing the X, so if you keep submitting the tab may reappear at end of tab bar.
NoNav	No gamepad/keyboard navigation within the window and no focusing toward this window with gamepad/keyboard navigation.
NoDecoration	Disable title-bar, resizing borders, and scrollbar.
NoInputs	Window is completely sealed and won’t receive inputs.

class ImGui.TabBarFlags¶

Enumeration of available tab bar flags.

Name	Description
None	No flags.
Reorderable	Allow manually dragging tabs to re-order them + New tabs are appended at the end of list.
AutoSelectNewTabs	Automatically select new tabs when they appear.
TabListPopupButton	Disable buttons to open the tab list popup.
NoCloseWithMiddleMouseButton	Disable behavior of closing tabs (that are submitted with p_open != NULL) with middle mouse button.
NoTabListScrollingButtons	Disable scrolling buttons (apply when fitting policy is ImGuiTabBarFlags_FittingPolicyScroll).
NoTooltip	Disable tooltips when hovering a tab.
FittingPolicyResizeDown	Resize tabs when they don’t fit.
FittingPolicyScroll	Add scroll buttons when tabs don’t fit.
FittingPolicyMask	Fitting policy mask (defaults to ImGuiTabBarFlags_FittingPolicyResizeDown \| ImGuiTabBarFlags_FittingPolicyScroll).
FittingPolicyDefault	Fitting policy when there are no tabs.

class ImGui.PopupFlags¶

Enumeration of available popup flags.

Name	Description
None	No flag set.
MouseButtonLeft	Open on Left Mouse release.
MouseButtonRight	Open on Right Mouse release.
MouseButtonMiddle	Open on Middle Mouse release.
MouseButtonMask	Bit mask for buttons.
MouseButtonDefault	Open on MouseButtonRight Mouse release (default).
NoOpenOverExistingPopup	Don’t open if there’s already a popup at the same level of the popup stack.
NoOpenOverItems	Don’t return true when hovering items, only when hovering empty space.
AnyPopupId	Ignore the ImGuiID parameter and test for any popup.
AnyPopupLevel	Search/test at any level of the popup stack.

class ImGui.InputTextFlags¶

Enumeration for input text flags.

Name	Description
None	No flags.
CharsDecimal	Allow decimals and operators (0123456789.+-/).
CharsHexadecimal	Allow decimals, operators ad letters (0123456789ABCDEFabcdef).
CharsUppercase	Turn lowercase letters into uppercase.
CharsNoBlank	Filter out spaces, tabs.
AutoSelectAll	Select entire text when first taking mouse focus.
EnterReturnsTrue	Return ‘true’ when Enter is pressed (as opposed to every time the value was modified).
CallbackCompletion	Callback on pressing TAB (for completion handling).
CallbackHistory	Callback on pressing Up/Down arrows (for history handling).
CallbackAlways	Callback on each iteration. User code may query cursor position, modify text buffer.
CallbackCharFilter	Callback on character inputs to replace or discard them. Modify ‘EventChar’ to replace or discard, or return 1 in callback to discard.
AllowTabInput	Pressing TAB input a ‘t’ character into the text field.
CtrlEnterForNewLine	In multi-line mode, unfocus with Enter, add new line with Ctrl+Enter (default is opposite unfocus with Ctrl+Enter, add line with Enter).
NoHorizontalScroll	Disable following the cursor horizontally.
AlwaysOverwrite	Overwrite mode.
ReadOnly	Read-only mode.
Password	Password mode, display all characters as ‘’.
NoUndoRedo	Disable undo/redo. Note that input text owns the text data while active, if you want to provide your own undo/redo stack you need e.g. to call ClearActiveID().
CharsScientific	Allow scientific notation input (0123456789.+-*/eE).
CallbackResize	Callback on buffer capacity changes request (beyond ‘buf_size’ parameter value), allowing the string to grow.
CallbackEdit	Callback on any edit.
EscapeClearsAll	Clears the input when Escape key is pressed.

class ImGui.SliderFlags¶

Enumeration for slider flags

Name	Description
None	No flag set.
AlwaysClamp	Clamp value to min/max bounds when input manually with CTRL+Click. By default CTRL+Click allows going out of bounds.
Logarithmic	Make the widget logarithmic (linear otherwise). Consider using ImGuiSliderFlags_NoRoundToFormat with this if using a format-string with small amount of digits.
NoRoundToFormat	Disable rounding underlying value to match precision of the display format string (e.g. %.3f values are rounded to those 3 digits).
NoInput	Disable CTRL+Click or Enter key allowing to input text directly into the widget.

class ImGui.SelectableFlags¶

Enum for selectable flags

Name	Description
None	No flag set.
DontClosePopups	Clicking this doesn’t close parent popup window.
SpanAllColumns	Selectable frame can span all columns (text will still fit in current column).
AllowDoubleClick	Generate press events on double clicks too.
Disabled	Cannot be selected, display grayed out text.
AllowItemOverlap	(WIP) Hit testing to allow subsequent widgets to overlap this one.

class ImGui.ColorEditFlags¶

Enumeration of flags for the color editing widgets.

Name	Description
None	No flag set.
NoAlpha	ColorEdit, ColorPicker, ColorButton: ignore Alpha component (will only read 3 components from the input pointer).
NoPicker	ColorEdit: disable picker when clicking on color square.
NoOptions	ColorEdit: disable toggling options menu when right-clicking on inputs/small preview.
NoSmallPreview	ColorEdit, ColorPicker: disable color square preview next to the inputs. (e.g. to show only the inputs)
NoInputs	ColorEdit, ColorPicker: disable inputs sliders/text widgets (e.g. to show only the small preview color square).
NoTooltip	ColorEdit, ColorPicker, ColorButton: disable tooltip when hovering the preview.
NoLabel	ColorEdit, ColorPicker: disable display of inline text label (the label is still forwarded to the tooltip and picker).
NoSidePreview	ColorPicker: disable bigger color preview on right side of the picker, use small color square preview instead.
NoDragDrop	ColorEdit: disable drag and drop target. ColorButton: disable drag and drop source.
NoBorder	ColorButton: disable border (which is enforced by default)
AlphaBar	ColorEdit, ColorPicker: show vertical alpha bar/gradient in picker.
AlphaPreview	ColorEdit, ColorPicker, ColorButton: display preview as a transparent color over a checkerboard, instead of opaque.
AlphaPreviewHalf	ColorEdit, ColorPicker, ColorButton: display half opaque / half checkerboard, instead of opaque.
HDR	ColorEdit: Currently only disable 0.0f..1.0f limits in RGBA edition (note: you probably want to use ImGuiColorEditFlags_Float flag as well).
DisplayRGB	ColorEdit: override display type among RGB.
DisplayHSV	ColorEdit: override display type among HSV.
DisplayHex	ColorEdit: override display type among Hex.
Uint8	Display values formatted as 0..255.
Float	Display values formatted as 0.0f..1.0f floats instead of 0..255 integers. No round-trip of value via integers.
PickerHueBar	Display a bar for Hue and rectangle for Sat/Value.
PickerHueWheel	Display a wheel for Hue and triangle for Sat/Value.
InputRGB	Input and output data in RGB format.
InputHSV	Input and output data in HSV format.

class ImGui.MouseButton¶

Enumeration for mouse button events.

Name	Description
Left	Index for the left mouse button.
Right	Index for the right mouse button.
Middle	Index for the middle mouse button.
COUNT	The number of mouse buttons.

class ImGui.MouseCursor¶

Enumeration of mouse cursor types for use with SetMouseCursor().

Name	Description
None	No cursor.
Arrow	Arrow cursor.
TextInput	Text input I-beam cursor.
ResizeAll	(Unused by Dear ImGui functions).
ResizeNS	Vertical resize cursor.
ResizeEW	Horizontal resize cursor.
ResizeNESW	Cursor for resizing bottom-left corner of window.
ResizeNWSE	Cursor for resizing bottom-right corner of window.
Hand	Sets mouse cursor to hand.
NotAllowed	Cursor for disallowed interaction (usually a crossed circle).
COUNT	Number of cursor types.

Examples¶

Creating Menu bars¶

local Imgui = require 'engine/imgui'
local Controller = Class.new(Entity)

function Controller:rendergui()
    -- Begins a new main menu bar on top of the screen
    if (Imgui.beginMainMenuBar()) then
        if (Imgui.beginMenu("File")) then
            if (Imgui.menuItem("New", "Open New File")) then
                -- new file logic here
            end
            if (Imgui.menuItem("Open", "Open New File")) then
                -- open file logic here
            end
            if (Imgui.menuItem("Save", "Save File")) then
                -- save file logic here
            end
            Imgui.endMenu()
        end
        if (Imgui.beginMenu("Edit", "Edit File")) then
            if (Imgui.menuItem("Undo", "Undo Change")) then
                -- undo logic here
            end
            if (Imgui.menuItem("Redo", "Redo change")) then
                -- redo logic here
            end
            Imgui.endMenu()
        end
        Imgui.endMainMenuBar()
    end

    -- Dialog with menu bar (outside the main menu bar condition)
    if (Imgui.beginDialog("Dialog Menu Test", 200, 100, Imgui.WindowFlags.MenuBar)) then
        if (Imgui.beginMenuBar()) then
            -- Need to use beginMenu for dropdown menus
            if (Imgui.beginMenu("Objects")) then
                if (Imgui.menuItem("Meshes", "Add Mesh")) then
                    -- mesh logic here
                end
                if (Imgui.menuItem("Materials", "Add Material")) then
                    -- material logic here
                end
                Imgui.endMenu()  -- Don't forget to end the menu
            end

            if (Imgui.beginMenu("PostFx")) then
                if (Imgui.menuItem("Bloom", "Add Bloom")) then
                    -- bloom effect logic here
                end
                if (Imgui.menuItem("Depth of Field", "Add DoF")) then
                    -- DoF logic here
                end
                Imgui.endMenu()  -- Don't forget to end the menu
            end
            Imgui.endMenuBar()  -- End the menu bar
        end

        Imgui.text("Dialog menu test")
        -- Rest of dialog content here

        Imgui.endDialog()
    end
end

return Controller

Using Groups and Child¶

local Imgui = require 'engine/imgui'
local Controller = Class.new(Entity)

function Controller:rendergui()
    -- First dialog with child window example (positioned to the left)
    if (Imgui.beginDialog("Child Window Example", 550, 650, Imgui.WindowFlags.MenuBar)) then
        -- Add a menu bar to the dialog
        if (Imgui.beginMenuBar()) then
            if (Imgui.beginMenu("File")) then
                if (Imgui.menuItem("Save", "Save content")) then
                    -- Save logic
                end
                if (Imgui.menuItem("Load", "Load content")) then
                    -- Load logic
                end
                Imgui.endMenu()
            end

            if (Imgui.beginMenu("View")) then
                if (Imgui.menuItem("Refresh", "Refresh content")) then
                    -- Refresh logic
                end
                Imgui.endMenu()
            end
            Imgui.endMenuBar()
        end

        -- Add title with some padding
        Imgui.spacing()
        Imgui.text("CHILD WINDOW EXAMPLE")
        Imgui.separator()
        Imgui.spacing()

        -- Make child window slightly smaller to ensure padding
        if (Imgui.beginChild("Scrolling", 520, 480, true)) then
            for n=1,30,1 do
                Imgui.text("Scrollable content item " .. n)

                if (n % 5 == 0) then
                    -- Imgui.pushItemWidth(200)  -- Control width of buttons
                    if (Imgui.button("Button " .. n)) then
                        -- Button action logic
                    end
                    -- Imgui.popItemWidth()
                    Imgui.spacing()
                end
            end

            Imgui.endChild()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()
        Imgui.text("Footer content")

        -- Center the close button
        local windowWidth = 550
        local buttonWidth = 100
        -- Imgui.setCursorPosX((windowWidth - buttonWidth) / 2)
        if (Imgui.button("Close", buttonWidth, 30)) then
            -- Close logic
        end

        Imgui.endDialog()
    end

    -- Second dialog with group example (positioned to the right)
    if (Imgui.beginDialog("Group Example", 600, 400)) then
        -- Add title with some padding
        Imgui.spacing()
        Imgui.text("GROUP LAYOUT EXAMPLE")
        Imgui.separator()
        Imgui.spacing()

        -- Create the first group
        Imgui.beginGroup()
        Imgui.text("Group 1")
        Imgui.spacing()
        -- Imgui.pushItemWidth(150)  -- Consistent control width
        if (Imgui.button("Button 1", 150, 30)) then
            -- Button 1 logic
        end
        Imgui.spacing()
        if (Imgui.button("Button 2", 150, 30)) then
            -- Button 2 logic
        end
        Imgui.spacing()
        -- Add a slider to the first group
        local value1 = 50 -- This should be a class variable in practice
        -- value1 = Imgui.sliderFloat("Slider 1", value1, 0, 100)
        -- Imgui.popItemWidth()
        Imgui.endGroup()

        -- Place the second group on the same line with ample spacing
        Imgui.sameLine(250) -- Add more spacing between groups

        -- Create the second group
        Imgui.beginGroup()
        Imgui.text("Group 2")
        Imgui.spacing()
        -- Imgui.pushItemWidth(150)  -- Consistent control width
        if (Imgui.button("Button 3", 150, 30)) then
            -- Button 3 logic
        end
        Imgui.spacing()
        if (Imgui.button("Button 4", 150, 30)) then
            -- Button 4 logic
        end
        Imgui.spacing()
        -- Add a checkbox to the second group
        local checked = false -- This should be a class variable in practice
        -- checked = Imgui.checkbox("Option 1", checked)
        -- Imgui.popItemWidth()
        Imgui.endGroup()

        -- Add a visual separator with ample spacing
        Imgui.spacing()
        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()
        Imgui.spacing()

        -- Create a third group below
        Imgui.text("Groups can also be used for vertical layout:")
        Imgui.spacing()

        -- Center this group
        local windowWidth = 600
        local groupWidth = 400
        -- Imgui.setCursorPosX((windowWidth - groupWidth) / 2)

        Imgui.beginGroup()
        Imgui.text("Group 3 - Controls")
        Imgui.spacing()
        if (Imgui.button("Save Settings", 180, 30)) then
            -- Save settings logic
        end
        Imgui.sameLine(200)
        if (Imgui.button("Load Settings", 180, 30)) then
            -- Load settings logic
        end
        Imgui.endGroup()

        Imgui.spacing()
        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Center the close button
        -- Imgui.setCursorPosX((windowWidth - 100) / 2)
        if (Imgui.button("Close Dialog", 100, 30)) then
            -- Close dialog logic
        end

        Imgui.endDialog()
    end
end

return Controller

Using Tables¶

local Imgui = require 'engine/imgui'
local TableController = Class.new(Entity)

function TableController:rendergui()
    -- Demo dialog with table examples
    if (Imgui.beginDialog("Table Examples")) then
        -- Add title with some padding
        Imgui.spacing()
        Imgui.text("TABLE INTERFACE EXAMPLES")
        Imgui.separator()
        Imgui.spacing()

        -- Basic Table Example
        Imgui.text("Basic 3-Column Table Example:")
        Imgui.spacing()

        if (Imgui.beginTable("BasicTable", 3)) then
            -- Table headers
            Imgui.tableNextColumn()
            Imgui.text("Name")
            Imgui.tableNextColumn()
            Imgui.text("Value")
            Imgui.tableNextColumn()
            Imgui.text("Description")

            -- First row
            Imgui.tableNextRow()
            Imgui.tableNextColumn()
            Imgui.text("Item 1")
            Imgui.tableNextColumn()
            Imgui.text("42")
            Imgui.tableNextColumn()
            Imgui.text("First item description")

            -- Second row
            Imgui.tableNextRow()
            Imgui.tableNextColumn()
            Imgui.text("Item 2")
            Imgui.tableNextColumn()
            Imgui.text("75")
            Imgui.tableNextColumn()
            Imgui.text("Second item description")

            -- Third row
            Imgui.tableNextRow()
            Imgui.tableNextColumn()
            Imgui.text("Item 3")
            Imgui.tableNextColumn()
            Imgui.text("150")
            Imgui.tableNextColumn()
            Imgui.text("Third item description")

            Imgui.endTable()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Table with interactive elements
        Imgui.text("Table with Interactive Elements:")
        Imgui.spacing()

        if (Imgui.beginTable("InteractiveTable", 3)) then
            -- Table headers
            Imgui.tableNextColumn()
            Imgui.text("Control")
            Imgui.tableNextColumn()
            Imgui.text("Status")
            Imgui.tableNextColumn()
            Imgui.text("Action")

            -- Row 1
            Imgui.tableNextRow()
            Imgui.tableNextColumn()
            Imgui.text("Option A")
            Imgui.tableNextColumn()
            Imgui.text("Enabled")
            Imgui.tableNextColumn()
            if (Imgui.button("Disable A", 100, 25)) then
                -- Disable logic
            end

            -- Row 2
            Imgui.tableNextRow()
            Imgui.tableNextColumn()
            Imgui.text("Option B")
            Imgui.tableNextColumn()
            Imgui.text("Disabled")
            Imgui.tableNextColumn()
            if (Imgui.button("Enable B", 100, 25)) then
                -- Enable logic
            end

            -- Row 3
            Imgui.tableNextRow()
            Imgui.tableNextColumn()
            Imgui.text("Option C")
            Imgui.tableNextColumn()
            Imgui.text("Enabled")
            Imgui.tableNextColumn()
            if (Imgui.button("Disable C", 100, 25)) then
                -- Disable logic
            end

            Imgui.endTable()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Data Table Example
        Imgui.text("Data Entry Table Example:")
        Imgui.spacing()

        -- Use columns as an alternative layout option
        Imgui.createColumns(2)

        -- Left column - table
        if (Imgui.beginTable("DataTable", 2)) then
            -- Headers
            Imgui.tableNextColumn()
            Imgui.text("Parameter")
            Imgui.tableNextColumn()
            Imgui.text("Value")

            -- Generate some data rows
            for i=1,6,1 do
                Imgui.tableNextRow()
                Imgui.tableNextColumn()
                Imgui.text("Parameter " .. i)
                Imgui.tableNextColumn()
                Imgui.text(tostring(i * 10))
            end

            Imgui.endTable()
        end

        -- Move to the second column
        Imgui.moveToNextColumn()

        -- Right column - controls
        Imgui.text("Controls:")
        Imgui.spacing()

        if (Imgui.button("Add Row", 120, 30)) then
            -- Add row logic
        end

        Imgui.spacing()

        if (Imgui.button("Remove Row", 120, 30)) then
            -- Remove row logic
        end

        Imgui.spacing()

        if (Imgui.button("Update Values", 120, 30)) then
            -- Update values logic
        end

        -- Reset columns
        Imgui.createColumns(1)

        Imgui.spacing()
        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Footer with button
        if (Imgui.button("Close", 100, 30)) then
            -- Close dialog logic
        end

        Imgui.endDialog()
    end
end

return TableController

Using the Tab Bar element.¶

local Imgui = require 'engine/imgui'
local TabBarController = Class.new(Entity)

function TabBarController:rendergui()
    -- Demo dialog with various tab bar examples
    Imgui.setNextWindowSize(750,850)
    if (Imgui.beginDialog("Tab Bar Examples")) then
        -- Add title with some padding
        Imgui.spacing()
        Imgui.text("TAB BAR INTERFACE EXAMPLES")
        Imgui.separator()
        Imgui.spacing()

        -- Define some colors for use in our tabs (commented out until createColor is supported)
        -- local colorBlue = Imgui.createColor(0, 0.5, 1, 1)
        -- local colorGreen = Imgui.createColor(0, 0.8, 0, 1)
        -- local colorRed = Imgui.createColor(1, 0, 0, 1)
        -- local colorYellow = Imgui.createColor(1, 0.9, 0, 1)

        -- Basic Tab Bar Example
        Imgui.text("Basic Tab Bar:")
        Imgui.spacing()

        if (Imgui.beginTabBar("BasicTabBar", Imgui.TabBarFlags.None)) then
            -- First tab
            if (Imgui.beginTabItem("Overview")) then
                Imgui.spacing()
                Imgui.text("This is a basic tab bar example.")
                Imgui.spacing()
                Imgui.text("Each tab contains different content and can be selected by clicking on the tab header.")
                Imgui.spacing()
                -- Using regular text instead of colored text
                Imgui.text("Try clicking on the other tabs to see their content!")
                -- Imgui.textColored("Try clicking on the other tabs to see their content!", colorBlue)
                Imgui.endTabItem()
            end

            -- Second tab
            if (Imgui.beginTabItem("Details")) then
                Imgui.spacing()
                Imgui.text("Tab Details:")
                Imgui.spacing()
                Imgui.text("- Tabs organize content into separate sections")
                Imgui.text("- Only one tab is visible at a time")
                Imgui.text("- Tabs can contain any UI elements")
                Imgui.spacing()

                if (Imgui.button("Click Me!", 120, 30)) then
                    -- Button action logic
                end

                Imgui.endTabItem()
            end

            -- Third tab
            if (Imgui.beginTabItem("Help")) then
                Imgui.spacing()
                Imgui.text("Tab Navigation:")
                Imgui.spacing()
                Imgui.text("- Click on tab headers to switch between tabs")
                Imgui.text("- Each tab maintains its own state")
                Imgui.endTabItem()
            end

            Imgui.endTabBar()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Advanced Tab Bar with Flags
        Imgui.text("Advanced Tab Bar with Flags:")
        Imgui.spacing()

        -- Combining multiple flags
        local tabFlags = Imgui.TabBarFlags.Reorderable + Imgui.TabBarFlags.AutoSelectNewTabs

        if (Imgui.beginTabBar("AdvancedTabBar", tabFlags)) then
            -- Data tab
            if (Imgui.beginTabItem("Data", Imgui.TabBarFlags.None)) then
                Imgui.spacing()
                Imgui.text("Data View")
                Imgui.spacing()

                -- Add a table inside the tab
                if (Imgui.beginTable("DataTable", 3)) then
                    -- Table headers
                    Imgui.tableNextColumn()
                    Imgui.text("Name")
                    -- Imgui.textColored("Name", colorBlue)
                    Imgui.tableNextColumn()
                    Imgui.text("Value")
                    -- Imgui.textColored("Value", colorBlue)
                    Imgui.tableNextColumn()
                    Imgui.text("Status")
                    -- Imgui.textColored("Status", colorBlue)

                    -- Row 1
                    Imgui.tableNextRow()
                    Imgui.tableNextColumn()
                    Imgui.text("Alpha")
                    Imgui.tableNextColumn()
                    Imgui.text("42")
                    Imgui.tableNextColumn()
                    Imgui.text("Active")
                    -- Imgui.textColored("Active", colorGreen)

                    -- Row 2
                    Imgui.tableNextRow()
                    Imgui.tableNextColumn()
                    Imgui.text("Beta")
                    Imgui.tableNextColumn()
                    Imgui.text("78")
                    Imgui.tableNextColumn()
                    Imgui.text("Pending")
                    -- Imgui.textColored("Pending", colorYellow)

                    -- Row 3
                    Imgui.tableNextRow()
                    Imgui.tableNextColumn()
                    Imgui.text("Gamma")
                    Imgui.tableNextColumn()
                    Imgui.text("15")
                    Imgui.tableNextColumn()
                    Imgui.text("Inactive")
                    -- Imgui.textColored("Inactive", colorRed)

                    Imgui.endTable()
                end

                Imgui.spacing()
                Imgui.text("This tab demonstrates a data view with a table.")
                Imgui.text("Try dragging this tab to reorder it (Reorderable flag is enabled).")

                Imgui.endTabItem()
            end

            -- Settings tab
            if (Imgui.beginTabItem("Settings", Imgui.TabBarFlags.None)) then
                Imgui.spacing()
                Imgui.text("Settings Panel")
                Imgui.spacing()

                -- Create columns for settings
                Imgui.createColumns(2)

                -- Left column
                Imgui.text("General Settings:")
                Imgui.spacing()

                if (Imgui.button("Save Configuration", 150, 30)) then
                    -- Save config logic
                end

                Imgui.spacing()

                if (Imgui.button("Load Configuration", 150, 30)) then
                    -- Load config logic
                end

                -- Move to right column
                Imgui.moveToNextColumn()

                Imgui.text("Display Settings:")
                Imgui.spacing()

                if (Imgui.button("Set Resolution", 150, 30)) then
                    -- Resolution logic
                end

                Imgui.spacing()

                if (Imgui.button("Toggle Fullscreen", 150, 30)) then
                    -- Fullscreen logic
                end

                -- Reset columns
                Imgui.createColumns(1)

                Imgui.spacing()
                Imgui.separator()
                Imgui.spacing()
                Imgui.text("This tab demonstrates settings with a column layout.")

                Imgui.endTabItem()
            end

            -- Statistics tab
            if (Imgui.beginTabItem("Statistics", Imgui.TabBarFlags.None)) then
                Imgui.spacing()
                Imgui.text("Statistics View")
                Imgui.spacing()

                -- Use a child window for scrollable content
                if (Imgui.beginChild("StatsContent", 0, 200, true)) then
                    Imgui.text("Performance Metrics:")
                    Imgui.spacing()

                    for i=1,10,1 do
                        Imgui.text("Metric " .. i .. ": " .. math.random(10, 100) .. "%")
                        Imgui.spacing()
                    end

                    Imgui.endChild()
                end

                Imgui.spacing()
                Imgui.text("This tab demonstrates scrollable content in a child window.")

                Imgui.endTabItem()
            end

            Imgui.endTabBar()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Nested Tab Bars Example
        Imgui.text("Nested Tab Bars:")
        Imgui.spacing()

        if (Imgui.beginTabBar("OuterTabBar", Imgui.TabBarFlags.None)) then
            -- First outer tab
            if (Imgui.beginTabItem("Main")) then
                Imgui.spacing()
                Imgui.text("Main Content")
                Imgui.spacing()

                -- Nested inner tab bar
                if (Imgui.beginTabBar("InnerTabBar", Imgui.TabBarFlags.None)) then
                    -- First inner tab
                    if (Imgui.beginTabItem("Sub-A")) then
                        Imgui.spacing()
                        Imgui.text("This is Sub-section A")
                        Imgui.spacing()
                        Imgui.text("Nested tab bars can help organize complex interfaces.")
                        Imgui.endTabItem()
                    end

                    -- Second inner tab
                    if (Imgui.beginTabItem("Sub-B")) then
                        Imgui.spacing()
                        Imgui.text("This is Sub-section B")
                        Imgui.spacing()

                        if (Imgui.button("Action B", 100, 30)) then
                            -- Action logic
                        end

                        Imgui.endTabItem()
                    end

                    -- Third inner tab
                    if (Imgui.beginTabItem("Sub-C")) then
                        Imgui.spacing()
                        Imgui.text("This is Sub-section C")
                        Imgui.spacing()
                        Imgui.text("Nested tabs can go multiple levels deep if needed.")
                        -- Imgui.textColored("Nested tabs can go multiple levels deep if needed.", colorBlue)
                        Imgui.endTabItem()
                    end

                    Imgui.endTabBar()
                end

                Imgui.endTabItem()
            end

            -- Second outer tab
            if (Imgui.beginTabItem("Options")) then
                Imgui.spacing()
                Imgui.text("Options Panel")
                Imgui.spacing()

                if (Imgui.button("Apply", 100, 30)) then
                    -- Apply logic
                end

                Imgui.sameLine(120)

                if (Imgui.button("Reset", 100, 30)) then
                    -- Reset logic
                end

                Imgui.endTabItem()
            end

            Imgui.endTabBar()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Footer with button
        if (Imgui.button("Close", 100, 30)) then
            -- Close dialog logic
        end

        Imgui.endDialog()
    end
end

return TabBarController

Creating different types of popups.¶

local Imgui = require 'engine/imgui'
local PopupController = Class.new(Entity)

function PopupController:rendergui()
    -- Demo dialog with various popup examples
    if (Imgui.beginDialog("Popup Examples")) then
        -- Add title with some padding
        Imgui.spacing()
        Imgui.text("POPUP INTERFACE EXAMPLES")
        Imgui.separator()
        Imgui.spacing()

        -- Basic Popup Example
        Imgui.text("Basic Popup:")
        Imgui.spacing()

        if (Imgui.button("Open Basic Popup", 150, 30)) then
            Imgui.openPopup("BasicPopup")
        end

        -- Basic popup implementation
        if (Imgui.beginPopup("BasicPopup")) then
            Imgui.text("This is a basic popup!")
            Imgui.spacing()
            Imgui.text("Popups appear over the current window")
            Imgui.text("and capture keyboard/mouse inputs.")
            Imgui.spacing()

            if (Imgui.button("Close", 100, 30)) then
                Imgui.closeCurrentPopup()
            end

            Imgui.endPopup()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Context Menu Popup Example
        Imgui.text("Context Menu Popup (Right-click below):")
        Imgui.spacing()

        -- Create a rectangle or area where right-click will open the popup
        -- In actual implementation, you might have a visual element here
        Imgui.text("Right-click in this area to open context menu")

        -- Use PopupFlags.MouseButtonRight to open on right mouse button
        if (Imgui.beginPopup("ContextMenu", Imgui.PopupFlags.MouseButtonRight)) then
            Imgui.text("Context Menu")
            Imgui.separator()

            if (Imgui.button("Option 1", 120, 25)) then
                -- Option 1 logic
                Imgui.closeCurrentPopup()
            end

            if (Imgui.button("Option 2", 120, 25)) then
                -- Option 2 logic
                Imgui.closeCurrentPopup()
            end

            if (Imgui.button("Option 3", 120, 25)) then
                -- Option 3 logic
                Imgui.closeCurrentPopup()
            end

            Imgui.separator()

            if (Imgui.button("Cancel", 120, 25)) then
                Imgui.closeCurrentPopup()
            end

            Imgui.endPopup()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Modal Popup Example
        Imgui.text("Modal Popup (blocks interaction with other windows):")
        Imgui.spacing()

        if (Imgui.button("Open Modal Dialog", 150, 30)) then
            Imgui.openPopup("ModalPopup")
        end

        -- Modal popup - blocks interaction with other windows until closed
        if (Imgui.beginPopupModal("ModalPopup")) then
            Imgui.text("This is a modal popup")
            Imgui.spacing()
            Imgui.text("Modal popups prevent interaction with other windows")
            Imgui.text("until they are closed. They're useful for important")
            Imgui.text("decisions or notifications that require attention.")
            Imgui.spacing()

            -- Create a simple form inside the modal
            Imgui.text("Enter value:")
            -- Here you would typically have an input field

            Imgui.spacing()
            Imgui.separator()
            Imgui.spacing()

            -- Buttons at the bottom
            if (Imgui.button("Confirm", 100, 30)) then
                -- Confirm action logic
                Imgui.closeCurrentPopup()
            end

            Imgui.sameLine(120)

            if (Imgui.button("Cancel", 100, 30)) then
                Imgui.closeCurrentPopup()
            end

            Imgui.endPopup()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Nested Popup Example
        Imgui.text("Nested Popups:")
        Imgui.spacing()

        if (Imgui.button("Open Parent Popup", 150, 30)) then
            Imgui.openPopup("ParentPopup")
        end

        -- Parent popup that contains a button to open a child popup
        if (Imgui.beginPopup("ParentPopup")) then
            Imgui.text("Parent Popup")
            Imgui.spacing()
            Imgui.text("This popup contains a button to open another popup.")
            Imgui.spacing()

            if (Imgui.button("Open Child Popup", 150, 30)) then
                Imgui.openPopup("ChildPopup")
            end

            -- Nested child popup
            if (Imgui.beginPopup("ChildPopup")) then
                Imgui.text("Child Popup")
                Imgui.spacing()
                Imgui.text("This is a popup inside another popup!")
                Imgui.spacing()

                if (Imgui.button("Close Child", 120, 30)) then
                    Imgui.closeCurrentPopup() -- Closes only the child popup
                end

                Imgui.endPopup()
            end

            Imgui.spacing()
            Imgui.separator()
            Imgui.spacing()

            if (Imgui.button("Close Parent", 120, 30)) then
                Imgui.closeCurrentPopup() -- Closes the parent popup
            end

            Imgui.endPopup()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Popup with Complex Content Example
        Imgui.text("Popup with Complex Content:")
        Imgui.spacing()

        if (Imgui.button("Open Complex Popup", 150, 30)) then
            Imgui.openPopup("ComplexPopup")
        end

        -- Popup containing more complex UI elements
        if (Imgui.beginPopup("ComplexPopup")) then
            Imgui.text("Complex Popup Example")
            Imgui.spacing()

            -- Create columns inside the popup
            Imgui.createColumns(2)

            -- Left column
            Imgui.text("Column 1")
            Imgui.spacing()

            if (Imgui.button("Button 1", 120, 30)) then
                -- Button 1 logic
            end

            Imgui.spacing()

            if (Imgui.button("Button 2", 120, 30)) then
                -- Button 2 logic
            end

            -- Right column
            Imgui.moveToNextColumn()

            Imgui.text("Column 2")
            Imgui.spacing()

            -- Add a table inside the popup
            if (Imgui.beginTable("PopupTable", 2)) then
                Imgui.tableNextColumn()
                Imgui.text("Name")
                Imgui.tableNextColumn()
                Imgui.text("Value")

                Imgui.tableNextRow()
                Imgui.tableNextColumn()
                Imgui.text("Item 1")
                Imgui.tableNextColumn()
                Imgui.text("100")

                Imgui.tableNextRow()
                Imgui.tableNextColumn()
                Imgui.text("Item 2")
                Imgui.tableNextColumn()
                Imgui.text("200")

                Imgui.endTable()
            end

            -- Reset columns
            Imgui.createColumns(1)

            Imgui.spacing()
            Imgui.separator()
            Imgui.spacing()

            if (Imgui.button("Close", 100, 30)) then
                Imgui.closeCurrentPopup()
            end

            Imgui.endPopup()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- File Menu Popup Example
        Imgui.text("Menu-Style Popup:")
        Imgui.spacing()

        if (Imgui.button("Show File Menu", 150, 30)) then
            Imgui.openPopup("FileMenuPopup")
        end

        -- Menu-style popup
        if (Imgui.beginPopup("FileMenuPopup")) then
            Imgui.text("File")
            Imgui.separator()

            if (Imgui.button("New", 100, 25)) then
                -- New file logic
                Imgui.closeCurrentPopup()
            end

            if (Imgui.button("Open...", 100, 25)) then
                -- Open file logic
                Imgui.closeCurrentPopup()
            end

            if (Imgui.button("Save", 100, 25)) then
                -- Save file logic
                Imgui.closeCurrentPopup()
            end

            if (Imgui.button("Save As...", 100, 25)) then
                -- Save as logic
                Imgui.closeCurrentPopup()
            end

            Imgui.separator()

            if (Imgui.button("Exit", 100, 25)) then
                -- Exit logic
                Imgui.closeCurrentPopup()
            end

            Imgui.endPopup()
        end

        Imgui.spacing()
        Imgui.separator()
        Imgui.spacing()

        -- Footer with button to close the dialog
        if (Imgui.button("Close Dialog", 120, 30)) then
            -- Close dialog logic
        end

        Imgui.endDialog()
    end
end

return PopupController

Accesing item states.¶

local Imgui = require 'engine/imgui'
local ItemStateController = Class.new(Entity)

function ItemStateController:init()
    -- State tracking for persistent UI behaviors
    self.showExtraInfo = {}      -- Track which nodes should show extra info
    self.clickCounter = {}       -- Track click counts for items
    self.hoveredItems = {}       -- Track which items were hovered last frame
end

function ItemStateController:rendergui()
    Imgui.beginDialog("Item State Functions Example")

    Imgui.text("This example demonstrates various item state functions:")
    Imgui.spacing()
    Imgui.text("- isItemHovered(): Detects when mouse is over an item")
    Imgui.text("- isItemClicked(): Detects when an item is clicked")
    Imgui.text("- isItemToggledOpen(): Detects when an item is freshly opened")
    Imgui.spacing()
    Imgui.separator()
    Imgui.spacing()

    -- SECTION 1: isItemHovered example
    Imgui.text("1. isItemHovered() Example:")
    Imgui.spacing()

    -- Button that changes appearance when hovered
    if Imgui.button("Hover over me", 150, 30) then
        -- Button action
    end

    -- Check if the button is being hovered
    if Imgui.isItemHovered() then
        Imgui.text("Button is currently being hovered!")
        -- Track this item as hovered for next frame
        self.hoveredItems["hover_button"] = true
    else
        if self.hoveredItems["hover_button"] then
            Imgui.text("Button was previously hovered")
        else
            Imgui.text("Button has not been hovered yet")
        end
    end

    Imgui.spacing()
    Imgui.separator()
    Imgui.spacing()

    -- SECTION 2: isItemClicked example
    Imgui.text("2. isItemClicked() Example:")
    Imgui.spacing()

    -- Initialize click counter if not exists
    if self.clickCounter["click_button"] == nil then
        self.clickCounter["click_button"] = 0
    end

    -- Button that counts clicks
    if Imgui.button("Click me", 150, 30) then
        -- Button action happens here (standard button behavior)
    end

    -- Check if the button was clicked this frame
    if Imgui.isItemClicked() then
        self.clickCounter["click_button"] = self.clickCounter["click_button"] + 1
    end

    -- Display click count (persistent across frames)
    Imgui.text("Button has been clicked " .. self.clickCounter["click_button"] .. " times")

    Imgui.spacing()
    Imgui.separator()
    Imgui.spacing()

    -- SECTION 3: isItemToggledOpen example with persistent state
    Imgui.text("3. isItemToggledOpen() Example:")
    Imgui.spacing()

    -- Tree node 1: Basic example that toggles persistent visibility
    local nodeId = "info_node"
    local isOpen = Imgui.treeNode("Click to toggle extra information")

    -- When node is first opened, update our persistent visibility state
    if isOpen and Imgui.isItemToggledOpen() then
        -- Toggle the visibility state when opened
        self.showExtraInfo[nodeId] = not self.showExtraInfo[nodeId]
    end

    if isOpen then
        -- Show basic content always visible when open
        Imgui.text("Basic information (always visible)")

        -- Show extra information if toggled on (persists across opening/closing)
        if self.showExtraInfo[nodeId] then
            Imgui.spacing()
            Imgui.text("EXTRA INFORMATION PANEL:")
            Imgui.text("This panel remains visible until you toggle it off")
            Imgui.text("by opening the tree node again.")

            -- Add a button to manually hide extra info
            if Imgui.button("Hide Extra Info", 150, 30) then
                self.showExtraInfo[nodeId] = false
            end
        else
            Imgui.spacing()
            Imgui.text("Extra information is currently hidden.")
            Imgui.text("Open and close this node to toggle visibility.")
        end

        Imgui.treePop()
    end

    -- Tree node 2: Combines all three behaviors
    Imgui.spacing()
    local nodeId2 = "combined_node"

    -- Initialize click counter if not exists
    if self.clickCounter[nodeId2] == nil then
        self.clickCounter[nodeId2] = 0
    end

    local isOpen2 = Imgui.treeNode("Combined example (hover, click, toggle)")

    -- Check if node was clicked (must be done immediately after creating the tree node)
    if Imgui.isItemClicked() then
        self.clickCounter[nodeId2] = self.clickCounter[nodeId2] + 1
    end

    -- Check if node is being hovered
    local isHovered = Imgui.isItemHovered()

    -- Check if node was just opened
    local wasJustToggled = Imgui.isItemToggledOpen()

    if isOpen2 then
        -- First check if this node was just opened
        if wasJustToggled then
            Imgui.text("Node was just opened!")
        end

        -- Show if the node is being hovered
        if isHovered then
            Imgui.text("Node is being hovered right now")
        end

        -- Show how many times this node has been clicked
        Imgui.text("This node has been clicked " .. self.clickCounter[nodeId2] .. " times")

        Imgui.treePop()
    end

    Imgui.endDialog()
end

return ItemStateController